NASA News: NASA's Fermi Finds Youngest Millisecond Pulsar, 100 Pulsars To-Date

WASHINGTON -- An international team of scientists using NASA's Fermi
Gamma-ray Space Telescope has discovered a surprisingly powerful
millisecond pulsar that challenges existing theories about how these objects form.

At the same time, another team has located nine new gamma-ray pulsars
in Fermi data, using improved analytical techniques.

A pulsar is a type of neutron star that emits electromagnetic energy
at periodic intervals. A neutron star is the closest thing to a black
hole that astronomers can observe directly, crushing half a million
times more mass than Earth into a sphere no larger than a city. This
matter is so compressed that even a teaspoonful weighs as much as
Mount Everest.

"With this new batch of pulsars, Fermi now has detected more than 100,
which is an exciting milestone when you consider that, before Fermi's
launch in 2008, only seven of them were known to emit gamma rays,"
said Pablo Saz Parkinson, an astrophysicist at the Santa Cruz
Institute for Particle Physics at the University of California Santa
Cruz, and a co-author on two papers detailing the findings.

One group of pulsars combines incredible density with extreme
rotation. The fastest of these so-called millisecond pulsars whirls
at 43,000 revolutions per minute.

Millisecond pulsars are thought to achieve such speeds because they
are gravitationally bound in binary systems with normal stars. During
part of their stellar lives, gas flows from the normal star to the
pulsar. Over time, the impact of this falling gas gradually spins up
the pulsar's rotation.

The strong magnetic fields and rapid rotation of pulsars cause them to
emit powerful beams of energy, from radio waves to gamma rays.
Because the star is transferring rotational energy to the pulsar, the
pulsar's spin eventually slows as the star loses matter.

Typically, millisecond pulsars are around a billion years old.
However, in the Nov. 3 issue of Science, the Fermi team reveals a
bright, energetic millisecond pulsar only 25 million years old.

The object, named PSR J1823−3021A, lies within NGC 6624, a spherical
collection of ancient stars called a globular cluster, one of about
160 similar objects that orbit our galaxy. The cluster is about 10
billion years old and lies about 27,000 light-years away toward the
constellation Sagittarius.

Fermi's Large Area Telescope (LAT) showed that eleven globular
clusters emit gamma rays, the cumulative emission of dozens of
millisecond pulsars too faint for even Fermi to detect individually.
But that's not the case for NGC 6624.

"It's amazing that all of the gamma rays we see from this cluster are
coming from a single object. It must have formed recently based on
how rapidly it's emitting energy. It's a bit like finding a screaming
baby in a quiet retirement home," said Paulo Freire, the study's lead
author, at the Max Planck Institute for Radio Astronomy in Bonn, Germany.

J1823−3021A was previously identified as a pulsar by its radio
emission, yet of the nine new pulsars, none are millisecond pulsars,
and only one was later found to emit radio waves.

Despite its sensitivity, Fermi's LAT may detect only one gamma ray for
every 100,000 rotations of some of these faint pulsars. Yet new
analysis techniques applied to the precise position and arrival time
of photons collected by the LAT since 2008 were able to identify them.

"We adapted methods originally devised for studying gravitational
waves to the problem of finding gamma-ray pulsars, and we were
quickly rewarded," said Bruce Allen, director of the Max Planck
Institute for Gravitational Physics in Hannover, Germany. Allen
co-authored a paper on the discoveries that was published online
today in The Astrophysical Journal.

Allen also directs the Einstein@Home project, a distributed computing
effort that uses downtime on computers of volunteers to process
astronomical data. In July, the project extended the search for
gamma-ray pulsars to the general public by including Femi LAT data in
the work processed by Einstein@Home users.

NASA's Fermi Gamma-ray Space Telescope is an astrophysics and particle
physics partnership. It is managed by NASA's Goddard Space Flight
Center in Greenbelt, Md. It was developed in collaboration with the
U.S. Department of Energy, with important contributions from academic
institutions and partners in France, Germany, Italy, Japan, Sweden
and the United States.

For more information, images and animations, please visit:



Media Invited To View Next J-2x Rocket Engine Test

BAY ST. LOUIS, Miss. -- Reporters are invited to NASA's John C.
Stennis Space Center in Mississippi on Wednesday, Nov. 9 to view a
test firing of the J-2X rocket engine, a key component of NASA's
Space Launch System, which will carry the Orion spacecraft, its crew,
cargo, equipment and science experiments beyond Earth orbit.

Designed for crew or cargo missions, the heavy-lift will be safe,
affordable and sustainable, and help NASA explore deep space.

To attend, reporters must contact Stennis public affairs at
228-688-3333 or e-mail rebecca.a.strecker@nasa.gov no later than noon
on Nov. 8. Media must arrive by 1 p.m. CST. The J-2X test is
scheduled for approximately 3 p.m.

Prior to the test, reporters may tour Pratt and Whitney Rocketdyne's
engine assembly facility, where J-2X engines are prepared for testing
and shipment. Following the test, media are invited to participate in
a news conference with NASA officials.

Media representatives not attending the test may submit questions for
the news conference to rebecca.a.strecker@nasa.gov. All questions
must be received no later than 11 a.m. Nov. 9.

Pratt and Whitney Rocketdyne is developing the J-2X engine for NASA's
Marshall Space Flight Center in Huntsville, Ala. The SLS rocket
engines will use a liquid hydrogen and liquid oxygen propulsion
system, which will include the J-2X engine for the upper stage and
RS-25D/E engines (space shuttle main engines) for the core stage.

The test also will air live on NASA TV at:


Engine test schedules are subject to change. If changes occur,
journalists who have responded will be notified via e-mail.

For more information about NASA's Space Launch System, visit:


For information about Stennis, visit:



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